The possibly deadly find was wrapped in a cardboard tube and tied with zip ties to a brick. Anthony called police, who cordoned off the area with the help of the bomb squad and safety retrieved the grenade.

“When I saw the picture of the device, I realized it was, indeed, a live grenade ... so was quite shocked,” said Former Brig. Gen. Rob Givens with the U.S. Air Force. “Even though it appears to be from a bygone time - perhaps from as far back as the second world war - those things still do go off.”

Givens believes the grenade may have fallen off a barge decades ago, or the person who had it eventually got nervous about it and tried to sink it with the brick.

The pineapple grenades were most commonly used between 1918 and 1945.

Shepard said he initially thought he found a time capsule and even tried to break it open with his shovel, something he stopped doing when he saw what it was.

While he was allowed to keep the casing the grenade came in, the Kentucky National Guard took the grenade and will now blow it up in a safe location.

How the grenade got to where it was found and who is responsible is still not known.